I choose an RCI Points package based upon the "underlying" fixed week. I want it to be at a nice resort, one that I would be happy to use each year. Or at least a week that has excellent rental potential. This way if you become dissatisfied with the RCI Points program, you can just drop out of it and revert back to owning the fixed week.
If the week trades through RCI, you can become an RCI Weeks member to do exchages. You can join a different exchange company, along with, or instead of, RCI. Or you can just use your week or rent it and have nothing whatsoever to do with RCI.
RCI has a long history of changing the "rules" and fees, often times without even letting members know. Their fees go up and the service goes down. They rent a lot of weeks to the general public for profit, thus making many prime weeks deposited by members unavailable for exchange. There is a major class action lawsuit going on now accusing RCI of engaging in these practises to the detriment of their dues-paying members.
The less beholden you are to RCI, the better. There's no guarantee of what you will get with RCI Points. But if you own a Points package with an underlying good week, you can walk away from RCI if you don't like the way things are going.